Speciation of Gold Nanoparticles by Ex Situ Extended X‑ray Absorption Fine Structure and X‑ray Absorption Near Edge Structure
journal contributionposted on 09.06.2016, 00:00 by Marco Giorgetti, Giuliana Aquilanti, Barbara Ballarin, Mario Berrettoni, Maria Cristina Cassani, Silvia Fazzini, Daniele Nanni, Domenica Tonelli
A combined X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) methodology is here presented on a series of partially and fully reduced AuIII samples. This allows monitoring the relative fraction of AuIII and Au0 in the studied samples, displaying a consistent and independent outcome. The strategy followed is based, for the first time, on two structural models that can be fitted simultaneously, and it evaluates the correlation among strongly correlated parameters such as coordination number and the Debye–Waller factor. The results of the present EXAFS and XANES approach can be extended to studies based on X-ray absorption spectroscopy experiments for the in situ monitoring of the formation of gold nanoclusters.